This invention is directed to keyboard sandwiches which are sealed together. In the preferred form of the disclosure the keyboard is hermetically sealed from the outside atmosphere to prevent contamination of the interior contacting parts thereof.
In addition, in certain instances, e.g., in certain military applications, the interior thereof is also pressure vented to facilitate operation at various atmospheric pressures, e.g., at high altitudes.
Keyboard structures such as shown in U.S. Pat. Nos. 3,860,771; 3,862,381 and 3,862,382 have gained wide acceptance. Such keyboard structures are held together by the keyboard frame via posts extending downwardly therefrom.
While such manner of construction is quite acceptable there has developed a demand for sealed keyboard structures which provide for contactor and contact isolation from the outside environment thereby preventing degradation thereof by moisture, etc.
The present invention provides such a keyboard construction as a sealed sandwich which in the preferred embodiment is hermetically sealed from the outside enviroment. To facilitate such construction and the proper functioning of the keyboard sandwich, there is provided herein a new and improved construction for permitting the passage of gas as an actuator portion thereof is depressed to force contactor means against contact means.
The present invention because of its sandwich construction is readily saleable absent a frame and thus may be incorporated into various structures e.g., calculators, machine control systems, telephones, radios and televisions for controlling the operation of same.